History storage device, history storage method and history storage program

According to the present invention, a write monitoring unit (22) stores data written for each address of a writing destination in a main storage device (13), when a write back operation for writing from a cache memory (12) to the main storage device (13) and a direct write operation for writing to the main storage device (13) not via the cache memory (12) are executed. When the periodic processings are finished, a history storage unit (24) stores, as history data, a grouped address and data of the writing destination, which are stored in a dirty line of the cache memory (12), and a grouped address and data stored by the write monitoring unit (22).